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  <script>
    // 比较运算符   >   <    >=   <=  ==  ===  !=  !==
    //比较运算符 返回的true和false 
    console.log(18 > 19)
    var x = 17;
    // console.log(16 <= x <= 18) //错误写法
    console.log(x >= 16 && x <= 18)

    // ==  === 的区别  == 只比较值是否相等   ===比较数据类型和值是否相等
    console.log("88" == 88) //true 
    console.log("88" === 88)//false
   // !=  !==   !=只比较值是否相等  !==比较数据类型和值是否相等

  </script>
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